(a) Field of the Invention
The present invention relates to a paper shredder cutting tool, and more particularly to a protruding ring protruding from a blade of each of the cutters. The protruding ring not only eliminates the need for spacer materials as used in prior art paper shredders, but also prevents a gap from forming between the two blades of each of the cutters because of thermal expansion and contraction when shredding paper, and thus the occurrence of paper jamming or wedging together of the upper and lower cutters.
(b) Description of the Prior Art
Referring to FIG. 1, which shows a traditional paper shredder cutting tool assembled from two sets of cylindrical rotary cutters 100, 100′, each set of which are structured from a plurality of spacers 102 and a shaft 103. Each of the spacers 102 is disposed between adjacent cutters 101, and the shaft 103 runs through the cutters 101 and the spacers 102, thereby assembling and forming the rotary cutters 100, 100′. Moreover, each of the cutters 101 is assembled from two blades 1011, 1012 juxtaposed and joined together. At least one blade tip 1013 is formed on a periphery of each of the two blades 1011, 1012, and a C-shaped paper chaff guide is circumferentially disposed on the spacers 102. Because a majority of the spacers 102 are fabricated from plastic material, when the paper shredder is shredding paper and producing heat, thus, the spacers 102 easily become fatigued and shrink due to thermal expansion and contraction, thereby causing an enlargement in the gap between the adjacent cutters 101, which not only results in paper jamming, but also wedging together of the upper and lower cutters.